The US Food and Drug Administration (FDA) has granted breakthrough therapy designation for a vaccine candidate for respiratory syncytial virus (RSV).
Bavarian Nordic’s MVA-BN RSV was granted the designation, which is designed to expedite the development and regulatory review of medicines to treat a serious condition, based on preliminary clinical evidence indicating that the vaccine candidate may demonstrate substantial improvement over available therapies.
Open Orphan subsidiary hVivo, conducted a Phase 2, double-blinded, placebo controlled human challenge trial to assess the vaccine candidate. That study provided a significant portion of this preliminary evidence.
The challenge study found a significant reduction in viral load in vaccinated subjects versus the placebo, and vaccinated subjects showed a significant reduction in clinical symptoms typically associated with RSV infections. It demonstarted a vaccine efficacy of up to 79 per cent in preventing symptomatic infections, and no vaccine-related serious adverse events were observed.
Open Orphan executive chairman Cathal Friel welcomed the breakthrough therapy designation.
“This highlights a major benefit of human challenge trials, in that they enable drug developers to obtain Phase 2/2a efficacy data for their vaccine and antivirals candidates in a fast, cost-effective manner ahead of larger scale studies,” he said. “This data can then strengthen submissions for important regulatory programmes such as the breakthrough therapy designation.”